Aquaponics is system of merging techniques of raising aquatic animals and hydroponic cultivation in order to mimic select characteristics of a natural symbiotic ecosystem.
Rather than letting aquatic animal waste accumulate, it is transferred through filters and into a hydroponic system supplying the crop with food. The filtering process allows nitrifying bacteria to break down the waste from nitrites into nitrates, a form the plants can absorb and utilize. After plant absorption, the water is then supplied back to the aquaculture system.
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Step 1: Material/Process Summary
This instructable is much more an experiment in which you can see me attempt to create a small model aquaponics system that could be manageable in one’s home or simply just for demonstration. I have never done anything involving hydroponics, aquaculture, or transporting water at all before, so this should be fun. Since I have had experience working with wood, I will use that as much of my structural material. (Though I am worried about woods distaste for being soaked) The container for the crop system will be a plastic window planter liner bought from any garden store. And the aquaculture container is a small cubic fish tank I found discounted at a local pet store.The nitrifying bacteria filter will be a PVC pipe container with "biofilter" screen bags which also can be found at pet stores.
- 9 feet 1x1
- particle board
- masonite board
- Risers of some sort if needed (I used 2x4s)
- plastic planter liner ( mine was 16" L. 5" H 8"W @ top)
- PVC with cap
- Little lava rocks for gardening.
- Bio filter bag
- Apprx 80 gph water pump w/ tubing
- 5.5" cubic fish tank.
- wood glue, spackle, paint, a few screws.
Step 2: Bio Filter (and Get a Better Phone or Camera)
Fishwaste being high in ammonia and nitrites, bacteria is necessary to break this down into plant appropriate foods. The chemical process is pictured here, but I honestly just think it looks interesting though I have no idea what is going on. But, this is an important step in the process. The bacteria though don’t float around in some additional pool, but need a home to live on. This means surfaces of relatively large area needs to be in contact with the water supplied from the fish environment. For my system, this is the PVC / bio filter container. There doesn’t seem to be anything special about the material inside the screen bag other than ample room and varying surfaces for bacteria to create colonies and begin work.
Step 3: Wood Structure
I am building the frame for the system with random boards and pine lumber since it's cheap material, and if this all proves to be a waste of time I will care a little less. But, this means that final surfaces that might be in contact with the water due to spillage or miscalculated flow will have to be waterproofed. To do this I will seal the exposed end grains and cracks with silicone and prime, paint, and polyurethane the flat surfaces towards the end of the construction process.
Step 4: Skeleton Frame
Based on the planter and fish tank being rectangular, the frame will begin with that end in mind. it needed to be wide enough to secure the planter, (and hide that ugly ass plastic), long enough for the fish tank at one end, and tall enough for gravity to assist in the water run off return.
The dimensions were 23.5"L x 9.25"W x 8.5" H
- I began with spare particle board, (adding 1x1 along each side due to the planter being wider than planned).
- Leaving enough area in the front for the fish tank (5.5")
- Screwed 2 x 4 risers for the planter to sit on
- 1x1 columns @ the corners as framing for thin masonite board siding.
- 1x1 "joist" @ top rear of frame for support
- Glue and clamp overnight or 8 hours.
Step 5: Plank Siding
Glue is set....
- Use a table saw, buzz saw, hand saw, whatever you got. cut the board siding. Full height of 8.5" and length of planter plus an inch for the 1x1 "joist" in the back.
- Attach with wood glue. clamping in place overnight or at least 8 hours again.
- Fill cracks and gaps with spackle. (for aesthetics really) but can help with silicone sealant later.
Step 6: Sanding Painting Sealing
(Looks bad. but not the worst.Going for functional not pretty)
- Sand down any abrasive surface, chunky spackle, etc.
- For flat surfaces, its beneficial to at least go over with a light sanding to increase grip for the paint
- Because the planter is white, decided to get a white paint n primer quart.
- Use small roller on the surfaces, brush for the cracks and corners.
- wait 2 hours for paint to dry.
- add polyurethane sealant, gloss/matte/satin up to you. and let sit for apprx 8 hours.
Step 7: Planter and Filter
For the planter I needed something that can support the plant and let the water run through. Hydroponic systems I have seen used small clay rocks. Since these were unavailable to me, I purchased small lava rocks that should produce the same effect. If there is a need for more volume, anything that supplies that volume without adding too much weight is preferred.
- fill the planter with low density porous soil substitute
- seal edges (if permanent placement) with silicone along the frame.
Step 8: Tank and Pump
The water pump's flow rate can vary, though you probably don't want anything over 300 gallons per hour. The flow rate needs to work with the filtering rate of your bio-filter. too much and it overflows into your planter. Not the end of the world but to be true to the aquaponic process it should match up.
If it is desired for the pump to not be visible, you can get a transfer pump. This will use tubing on one end and push the water through to another destination. The pump I have is a submersible, so it needs to be in the tank. Not ideal, but functional over aesthetics at the moment.
- Drill hole on edge of planter, wide enough for your rubber or plastic tubing, and feed into bio-filter
- Run along bottom of frame and and place pump into tank.
- easy enough.
Step 9: Turn It On
The water levels for both the planter and the tank need to be in a balance. The inflow from planter to tank needs to match outflow of tank to planter.
In reality, the system would be left with the introduction of nitrifying bacteria to begin colonizing. The bacteria need to be at a population that can convert the supplied ammonia. There would be a timeframe for cycling and testing the system for these levels before adding the crop and aquatic organisms. But let's just throw some plants in anyway because I am not going to be introducing any fish currently. Would rather avoid killing critters for an experimental project.
Step 10: .....waiting
currently waiting for DAP and paint to dry..... updating soon